Cook onion and garlic in shortening in Dutch Oven. Add beef and cook, stirring occasionally, to keep meat particles separated. Drain excess grease off. Mix in the soup, water and chili powder and cook a few minutes longer. Break spaghetti into inch pieces and stir into sauce until all covered. Bake for about 1 hour, but stir approximately every 15 minutes. Then add cheese to top. Bake another 15 minutes.